The P1151 code in a 2002 Ford Explorer indicates a problem with the oxygen sensor (O2 sensor) in bank 1, sensor 1. This sensor is located in the exhaust manifold and measures the amount of oxygen in the exhaust gases. If the sensor is faulty, it can cause the engine to run rich or lean, which can lead to decreased performance and fuel efficiency.
There are a few things that could cause the P1151 code to set, including:
* A faulty oxygen sensor
* A damaged or disconnected oxygen sensor wire
* An exhaust leak
To diagnose the problem, a mechanic will need to inspect the oxygen sensor and its wiring. If the sensor is faulty, it will need to be replaced. If the wiring is damaged or disconnected, it will need to be repaired or replaced. If there is an exhaust leak, it will need to be sealed.
Once the problem has been repaired, the check engine light should go off. If the light does not go off, it is recommended that you have the vehicle inspected by a mechanic to identify and fix any remaining issues.
